Sensitivity to allopurinol, which occurs in 10-15% of patients, can seriously limit the drug's use in chronic tophaceous gout. Oral allopurinol desensitization has been advocated for sensitive patients in whom use of the drug is warranted. We report the successful use of intravenous allopurinol desensitization in a patient with chronic tophaceous gout in whom oral desensitization had previously failed.